A hybrid vehicle may enter a regeneration mode or regenerative braking where the vehicle's kinetic energy is converted to electrical energy and stored for later use in response to a vehicle braking request. The hybrid vehicle driver may release an accelerator pedal and wait for a period of time before applying the brake pedal to request vehicle braking. Alternatively, the hybrid vehicle driver may release the accelerator pedal and apply vehicle brakes almost immediately. The different operating scenarios may make it more difficult for a transmission to select a desirable gear. Further, the hybrid vehicle's efficiency may be reduced if the transmission selects an undesirable gear because the engine and/or motor may not operate at a speed that is as efficient as is desired.
The inventors herein have recognized the above-mentioned issues and have developed an operating method for a vehicle, comprising: receiving data of an object or condition external the vehicle to a controller; and not permitting transmission shifting in response to the object external to the vehicle.
By not permitting transmission shifting between different ratios of a fixed ratio transmission, it may be possible to provide the technical result of reducing the possibility of perceived excessive transmission shifting which may lead to driver annoyance. Further, transmission shifting may be made more repeatable and expected for different driving conditions. In one example, one or more sensors may detect or predict vehicle braking and entry into a regenerative braking mode in response to objects or conditions in a vehicle's travel path. An object or condition in the vehicle's travel path may be indicative that the powertrain may shift multiple times in a short period of time if the transmission were permitted to shift during a vehicle braking sequence. The transmission may be held in its present gear during conditions where vehicle braking may be expected so that multiple short duration shifts may be avoided.
The present description may provide several advantages. For example, the approach may reduce a total actual number of transmission gear shifts during a time after an accelerator pedal is released and while the vehicle is in a regenerative braking mode. In addition, the approach may improve a driver's perception of vehicle operation. Further, the approach may anticipate vehicle braking or ignore selected conditions that may indicate the possibility of vehicle braking to improve transmission shifting.
The above advantages and other advantages, and features of the present description will be readily apparent from the following Detailed Description when taken alone or in connection with the accompanying drawings.
It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure.